Problem: Jessica is 5 times as old as Omar and is also 24 years older than Omar. How old is Jessica?
Solution: We can use the given information to write down two equations that describe the ages of Jessica and Omar. Let Jessica's current age be $j$ and Omar's current age be $o$ $j = 5o$ $j = o + 24$ Now we have two independent equations, and we can solve for our two unknowns. One way to solve for $j$ is to solve the second equation for $o$ and substitute that value into the first equation. Solving our second equation for $o$ , we get: $o = j - 24$ . Substituting this into our first equation, we get the equation: $j = 5$ $(j - 24)$ which combines the information about $j$ from both of our original equations. Simplifying the right side of this equation, we get: $j = 5j - 120$ Solving for $j$ , we get: $4 j = 120$ $j = 30$.